drivers/media/media-device.c

   1 /*
   2  * Media device
   3  *
   4  * Copyright (C) 2010 Nokia Corporation
   5  *
   6  * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
   7  *           Sakari Ailus <sakari.ailus@iki.fi>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  */
  18
  19 #include <linux/compat.h>
  20 #include <linux/export.h>
  21 #include <linux/idr.h>
  22 #include <linux/ioctl.h>
  23 #include <linux/media.h>
  24 #include <linux/slab.h>
  25 #include <linux/types.h>
  26 #include <linux/pci.h>
  27 #include <linux/usb.h>
  28 #include <linux/version.h>
  29
  30 #include <media/media-device.h>
  31 #include <media/media-devnode.h>
  32 #include <media/media-entity.h>
  33
  34 #ifdef CONFIG_MEDIA_CONTROLLER
  35
  36 /*
  37  * Legacy defines from linux/media.h. This is the only place we need this
  38  * so we just define it here. The media.h header doesn't expose it to the
  39  * kernel to prevent it from being used by drivers, but here (and only here!)
  40  * we need it to handle the legacy behavior.
  41  */
  42 #define MEDIA_ENT_SUBTYPE_MASK                  0x0000ffff
  43 #define MEDIA_ENT_T_DEVNODE_UNKNOWN             (MEDIA_ENT_F_OLD_BASE | \
  44                                                  MEDIA_ENT_SUBTYPE_MASK)
  45
  46 /* -----------------------------------------------------------------------------
  47  * Userspace API
  48  */
  49
  50 static inline void __user *media_get_uptr(__u64 arg)
  51 {
  52         return (void __user *)(uintptr_t)arg;
  53 }
  54
  55 static int media_device_open(struct file *filp)
  56 {
  57         return 0;
  58 }
  59
  60 static int media_device_close(struct file *filp)
  61 {
  62         return 0;
  63 }
  64
  65 static long media_device_get_info(struct media_device *dev, void *arg)
  66 {
  67         struct media_device_info *info = arg;
  68
  69         memset(info, 0, sizeof(*info));
  70
  71         if (dev->driver_name[0])
  72                 strlcpy(info->driver, dev->driver_name, sizeof(info->driver));
  73         else
  74                 strlcpy(info->driver, dev->dev->driver->name,
  75                         sizeof(info->driver));
  76
  77         strlcpy(info->model, dev->model, sizeof(info->model));
  78         strlcpy(info->serial, dev->serial, sizeof(info->serial));
  79         strlcpy(info->bus_info, dev->bus_info, sizeof(info->bus_info));
  80
  81         info->media_version = LINUX_VERSION_CODE;
  82         info->driver_version = info->media_version;
  83         info->hw_revision = dev->hw_revision;
  84
  85         return 0;
  86 }
  87
  88 static struct media_entity *find_entity(struct media_device *mdev, u32 id)
  89 {
  90         struct media_entity *entity;
  91         int next = id & MEDIA_ENT_ID_FLAG_NEXT;
  92
  93         id &= ~MEDIA_ENT_ID_FLAG_NEXT;
  94
  95         media_device_for_each_entity(entity, mdev) {
  96                 if (((media_entity_id(entity) == id) && !next) ||
  97                     ((media_entity_id(entity) > id) && next)) {
  98                         return entity;
  99                 }
 100         }
 101
 102         return NULL;
 103 }
 104
 105 static long media_device_enum_entities(struct media_device *mdev, void *arg)
 106 {
 107         struct media_entity_desc *entd = arg;
 108         struct media_entity *ent;
 109
 110         ent = find_entity(mdev, entd->id);
 111         if (ent == NULL)
 112                 return -EINVAL;
 113
 114         memset(entd, 0, sizeof(*entd));
 115
 116         entd->id = media_entity_id(ent);
 117         if (ent->name)
 118                 strlcpy(entd->name, ent->name, sizeof(entd->name));
 119         entd->type = ent->function;
 120         entd->revision = 0;             /* Unused */
 121         entd->flags = ent->flags;
 122         entd->group_id = 0;             /* Unused */
 123         entd->pads = ent->num_pads;
 124         entd->links = ent->num_links - ent->num_backlinks;
 125
 126         /*
 127          * Workaround for a bug at media-ctl <= v1.10 that makes it to
 128          * do the wrong thing if the entity function doesn't belong to
 129          * either MEDIA_ENT_F_OLD_BASE or MEDIA_ENT_F_OLD_SUBDEV_BASE
 130          * Ranges.
 131          *
 132          * Non-subdevices are expected to be at the MEDIA_ENT_F_OLD_BASE,
 133          * or, otherwise, will be silently ignored by media-ctl when
 134          * printing the graphviz diagram. So, map them into the devnode
 135          * old range.
 136          */
 137         if (ent->function < MEDIA_ENT_F_OLD_BASE ||
 138             ent->function > MEDIA_ENT_F_TUNER) {
 139                 if (is_media_entity_v4l2_subdev(ent))
 140                         entd->type = MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN;
 141                 else if (ent->function != MEDIA_ENT_F_IO_V4L)
 142                         entd->type = MEDIA_ENT_T_DEVNODE_UNKNOWN;
 143         }
 144
 145         memcpy(&entd->raw, &ent->info, sizeof(ent->info));
 146
 147         return 0;
 148 }
 149
 150 static void media_device_kpad_to_upad(const struct media_pad *kpad,
 151                                       struct media_pad_desc *upad)
 152 {
 153         upad->entity = media_entity_id(kpad->entity);
 154         upad->index = kpad->index;
 155         upad->flags = kpad->flags;
 156 }
 157
 158 static long media_device_enum_links(struct media_device *mdev, void *arg)
 159 {
 160         struct media_links_enum *links = arg;
 161         struct media_entity *entity;
 162
 163         entity = find_entity(mdev, links->entity);
 164         if (entity == NULL)
 165                 return -EINVAL;
 166
 167         if (links->pads) {
 168                 unsigned int p;
 169
 170                 for (p = 0; p < entity->num_pads; p++) {
 171                         struct media_pad_desc pad;
 172
 173                         memset(&pad, 0, sizeof(pad));
 174                         media_device_kpad_to_upad(&entity->pads[p], &pad);
 175                         if (copy_to_user(&links->pads[p], &pad, sizeof(pad)))
 176                                 return -EFAULT;
 177                 }
 178         }
 179
 180         if (links->links) {
 181                 struct media_link *link;
 182                 struct media_link_desc __user *ulink_desc = links->links;
 183
 184                 list_for_each_entry(link, &entity->links, list) {
 185                         struct media_link_desc klink_desc;
 186
 187                         /* Ignore backlinks. */
 188                         if (link->source->entity != entity)
 189                                 continue;
 190                         memset(&klink_desc, 0, sizeof(klink_desc));
 191                         media_device_kpad_to_upad(link->source,
 192                                                   &klink_desc.source);
 193                         media_device_kpad_to_upad(link->sink,
 194                                                   &klink_desc.sink);
 195                         klink_desc.flags = link->flags;
 196                         if (copy_to_user(ulink_desc, &klink_desc,
 197                                          sizeof(*ulink_desc)))
 198                                 return -EFAULT;
 199                         ulink_desc++;
 200                 }
 201         }
 202         memset(links->reserved, 0, sizeof(links->reserved));
 203
 204         return 0;
 205 }
 206
 207 static long media_device_setup_link(struct media_device *mdev, void *arg)
 208 {
 209         struct media_link_desc *linkd = arg;
 210         struct media_link *link = NULL;
 211         struct media_entity *source;
 212         struct media_entity *sink;
 213
 214         /* Find the source and sink entities and link.
 215          */
 216         source = find_entity(mdev, linkd->source.entity);
 217         sink = find_entity(mdev, linkd->sink.entity);
 218
 219         if (source == NULL || sink == NULL)
 220                 return -EINVAL;
 221
 222         if (linkd->source.index >= source->num_pads ||
 223             linkd->sink.index >= sink->num_pads)
 224                 return -EINVAL;
 225
 226         link = media_entity_find_link(&source->pads[linkd->source.index],
 227                                       &sink->pads[linkd->sink.index]);
 228         if (link == NULL)
 229                 return -EINVAL;
 230
 231         memset(linkd->reserved, 0, sizeof(linkd->reserved));
 232
 233         /* Setup the link on both entities. */
 234         return __media_entity_setup_link(link, linkd->flags);
 235 }
 236
 237 static long media_device_get_topology(struct media_device *mdev, void *arg)
 238 {
 239         struct media_v2_topology *topo = arg;
 240         struct media_entity *entity;
 241         struct media_interface *intf;
 242         struct media_pad *pad;
 243         struct media_link *link;
 244         struct media_v2_entity kentity, __user *uentity;
 245         struct media_v2_interface kintf, __user *uintf;
 246         struct media_v2_pad kpad, __user *upad;
 247         struct media_v2_link klink, __user *ulink;
 248         unsigned int i;
 249         int ret = 0;
 250
 251         topo->topology_version = mdev->topology_version;
 252
 253         /* Get entities and number of entities */
 254         i = 0;
 255         uentity = media_get_uptr(topo->ptr_entities);
 256         media_device_for_each_entity(entity, mdev) {
 257                 i++;
 258                 if (ret || !uentity)
 259                         continue;
 260
 261                 if (i > topo->num_entities) {
 262                         ret = -ENOSPC;
 263                         continue;
 264                 }
 265
 266                 /* Copy fields to userspace struct if not error */
 267                 memset(&kentity, 0, sizeof(kentity));
 268                 kentity.id = entity->graph_obj.id;
 269                 kentity.function = entity->function;
 270                 kentity.flags = entity->flags;
 271                 strlcpy(kentity.name, entity->name,
 272                         sizeof(kentity.name));
 273
 274                 if (copy_to_user(uentity, &kentity, sizeof(kentity)))
 275                         ret = -EFAULT;
 276                 uentity++;
 277         }
 278         topo->num_entities = i;
 279         topo->reserved1 = 0;
 280
 281         /* Get interfaces and number of interfaces */
 282         i = 0;
 283         uintf = media_get_uptr(topo->ptr_interfaces);
 284         media_device_for_each_intf(intf, mdev) {
 285                 i++;
 286                 if (ret || !uintf)
 287                         continue;
 288
 289                 if (i > topo->num_interfaces) {
 290                         ret = -ENOSPC;
 291                         continue;
 292                 }
 293
 294                 memset(&kintf, 0, sizeof(kintf));
 295
 296                 /* Copy intf fields to userspace struct */
 297                 kintf.id = intf->graph_obj.id;
 298                 kintf.intf_type = intf->type;
 299                 kintf.flags = intf->flags;
 300
 301                 if (media_type(&intf->graph_obj) == MEDIA_GRAPH_INTF_DEVNODE) {
 302                         struct media_intf_devnode *devnode;
 303
 304                         devnode = intf_to_devnode(intf);
 305
 306                         kintf.devnode.major = devnode->major;
 307                         kintf.devnode.minor = devnode->minor;
 308                 }
 309
 310                 if (copy_to_user(uintf, &kintf, sizeof(kintf)))
 311                         ret = -EFAULT;
 312                 uintf++;
 313         }
 314         topo->num_interfaces = i;
 315         topo->reserved2 = 0;
 316
 317         /* Get pads and number of pads */
 318         i = 0;
 319         upad = media_get_uptr(topo->ptr_pads);
 320         media_device_for_each_pad(pad, mdev) {
 321                 i++;
 322                 if (ret || !upad)
 323                         continue;
 324
 325                 if (i > topo->num_pads) {
 326                         ret = -ENOSPC;
 327                         continue;
 328                 }
 329
 330                 memset(&kpad, 0, sizeof(kpad));
 331
 332                 /* Copy pad fields to userspace struct */
 333                 kpad.id = pad->graph_obj.id;
 334                 kpad.entity_id = pad->entity->graph_obj.id;
 335                 kpad.flags = pad->flags;
 336                 kpad.index = pad->index;
 337
 338                 if (copy_to_user(upad, &kpad, sizeof(kpad)))
 339                         ret = -EFAULT;
 340                 upad++;
 341         }
 342         topo->num_pads = i;
 343         topo->reserved3 = 0;
 344
 345         /* Get links and number of links */
 346         i = 0;
 347         ulink = media_get_uptr(topo->ptr_links);
 348         media_device_for_each_link(link, mdev) {
 349                 if (link->is_backlink)
 350                         continue;
 351
 352                 i++;
 353
 354                 if (ret || !ulink)
 355                         continue;
 356
 357                 if (i > topo->num_links) {
 358                         ret = -ENOSPC;
 359                         continue;
 360                 }
 361
 362                 memset(&klink, 0, sizeof(klink));
 363
 364                 /* Copy link fields to userspace struct */
 365                 klink.id = link->graph_obj.id;
 366                 klink.source_id = link->gobj0->id;
 367                 klink.sink_id = link->gobj1->id;
 368                 klink.flags = link->flags;
 369
 370                 if (copy_to_user(ulink, &klink, sizeof(klink)))
 371                         ret = -EFAULT;
 372                 ulink++;
 373         }
 374         topo->num_links = i;
 375         topo->reserved4 = 0;
 376
 377         return ret;
 378 }
 379
 380 static long copy_arg_from_user(void *karg, void __user *uarg, unsigned int cmd)
 381 {
 382         /* All media IOCTLs are _IOWR() */
 383         if (copy_from_user(karg, uarg, _IOC_SIZE(cmd)))
 384                 return -EFAULT;
 385
 386         return 0;
 387 }
 388
 389 static long copy_arg_to_user(void __user *uarg, void *karg, unsigned int cmd)
 390 {
 391         /* All media IOCTLs are _IOWR() */
 392         if (copy_to_user(uarg, karg, _IOC_SIZE(cmd)))
 393                 return -EFAULT;
 394
 395         return 0;
 396 }
 397
 398 /* Do acquire the graph mutex */
 399 #define MEDIA_IOC_FL_GRAPH_MUTEX        BIT(0)
 400
 401 #define MEDIA_IOC_ARG(__cmd, func, fl, from_user, to_user)              \
 402         [_IOC_NR(MEDIA_IOC_##__cmd)] = {                                \
 403                 .cmd = MEDIA_IOC_##__cmd,                               \
 404                 .fn = (long (*)(struct media_device *, void *))func,    \
 405                 .flags = fl,                                            \
 406                 .arg_from_user = from_user,                             \
 407                 .arg_to_user = to_user,                                 \
 408         }
 409
 410 #define MEDIA_IOC(__cmd, func, fl)                                      \
 411         MEDIA_IOC_ARG(__cmd, func, fl, copy_arg_from_user, copy_arg_to_user)
 412
 413 /* the table is indexed by _IOC_NR(cmd) */
 414 struct media_ioctl_info {
 415         unsigned int cmd;
 416         unsigned short flags;
 417         long (*fn)(struct media_device *dev, void *arg);
 418         long (*arg_from_user)(void *karg, void __user *uarg, unsigned int cmd);
 419         long (*arg_to_user)(void __user *uarg, void *karg, unsigned int cmd);
 420 };
 421
 422 static const struct media_ioctl_info ioctl_info[] = {
 423         MEDIA_IOC(DEVICE_INFO, media_device_get_info, MEDIA_IOC_FL_GRAPH_MUTEX),
 424         MEDIA_IOC(ENUM_ENTITIES, media_device_enum_entities, MEDIA_IOC_FL_GRAPH_MUTEX),
 425         MEDIA_IOC(ENUM_LINKS, media_device_enum_links, MEDIA_IOC_FL_GRAPH_MUTEX),
 426         MEDIA_IOC(SETUP_LINK, media_device_setup_link, MEDIA_IOC_FL_GRAPH_MUTEX),
 427         MEDIA_IOC(G_TOPOLOGY, media_device_get_topology, MEDIA_IOC_FL_GRAPH_MUTEX),
 428 };
 429
 430 static long media_device_ioctl(struct file *filp, unsigned int cmd,
 431                                unsigned long __arg)
 432 {
 433         struct media_devnode *devnode = media_devnode_data(filp);
 434         struct media_device *dev = devnode->media_dev;
 435         const struct media_ioctl_info *info;
 436         void __user *arg = (void __user *)__arg;
 437         char __karg[256], *karg = __karg;
 438         long ret;
 439
 440         if (_IOC_NR(cmd) >= ARRAY_SIZE(ioctl_info)
 441             || ioctl_info[_IOC_NR(cmd)].cmd != cmd)
 442                 return -ENOIOCTLCMD;
 443
 444         info = &ioctl_info[_IOC_NR(cmd)];
 445
 446         if (_IOC_SIZE(info->cmd) > sizeof(__karg)) {
 447                 karg = kmalloc(_IOC_SIZE(info->cmd), GFP_KERNEL);
 448                 if (!karg)
 449                         return -ENOMEM;
 450         }
 451
 452         if (info->arg_from_user) {
 453                 ret = info->arg_from_user(karg, arg, cmd);
 454                 if (ret)
 455                         goto out_free;
 456         }
 457
 458         if (info->flags & MEDIA_IOC_FL_GRAPH_MUTEX)
 459                 mutex_lock(&dev->graph_mutex);
 460
 461         ret = info->fn(dev, karg);
 462
 463         if (info->flags & MEDIA_IOC_FL_GRAPH_MUTEX)
 464                 mutex_unlock(&dev->graph_mutex);
 465
 466         if (!ret && info->arg_to_user)
 467                 ret = info->arg_to_user(arg, karg, cmd);
 468
 469 out_free:
 470         if (karg != __karg)
 471                 kfree(karg);
 472
 473         return ret;
 474 }
 475
 476 #ifdef CONFIG_COMPAT
 477
 478 struct media_links_enum32 {
 479         __u32 entity;
 480         compat_uptr_t pads; /* struct media_pad_desc * */
 481         compat_uptr_t links; /* struct media_link_desc * */
 482         __u32 reserved[4];
 483 };
 484
 485 static long media_device_enum_links32(struct media_device *mdev,
 486                                       struct media_links_enum32 __user *ulinks)
 487 {
 488         struct media_links_enum links;
 489         compat_uptr_t pads_ptr, links_ptr;
 490         int ret;
 491
 492         memset(&links, 0, sizeof(links));
 493
 494         if (get_user(links.entity, &ulinks->entity)
 495             || get_user(pads_ptr, &ulinks->pads)
 496             || get_user(links_ptr, &ulinks->links))
 497                 return -EFAULT;
 498
 499         links.pads = compat_ptr(pads_ptr);
 500         links.links = compat_ptr(links_ptr);
 501
 502         ret = media_device_enum_links(mdev, &links);
 503         if (ret)
 504                 return ret;
 505
 506         if (copy_to_user(ulinks->reserved, links.reserved,
 507                          sizeof(ulinks->reserved)))
 508                 return -EFAULT;
 509         return 0;
 510 }
 511
 512 #define MEDIA_IOC_ENUM_LINKS32          _IOWR('|', 0x02, struct media_links_enum32)
 513
 514 static long media_device_compat_ioctl(struct file *filp, unsigned int cmd,
 515                                       unsigned long arg)
 516 {
 517         struct media_devnode *devnode = media_devnode_data(filp);
 518         struct media_device *dev = devnode->media_dev;
 519         long ret;
 520
 521         switch (cmd) {
 522         case MEDIA_IOC_ENUM_LINKS32:
 523                 mutex_lock(&dev->graph_mutex);
 524                 ret = media_device_enum_links32(dev,
 525                                 (struct media_links_enum32 __user *)arg);
 526                 mutex_unlock(&dev->graph_mutex);
 527                 break;
 528
 529         default:
 530                 return media_device_ioctl(filp, cmd, arg);
 531         }
 532
 533         return ret;
 534 }
 535 #endif /* CONFIG_COMPAT */
 536
 537 static const struct media_file_operations media_device_fops = {
 538         .owner = THIS_MODULE,
 539         .open = media_device_open,
 540         .ioctl = media_device_ioctl,
 541 #ifdef CONFIG_COMPAT
 542         .compat_ioctl = media_device_compat_ioctl,
 543 #endif /* CONFIG_COMPAT */
 544         .release = media_device_close,
 545 };
 546
 547 /* -----------------------------------------------------------------------------
 548  * sysfs
 549  */
 550
 551 static ssize_t show_model(struct device *cd,
 552                           struct device_attribute *attr, char *buf)
 553 {
 554         struct media_devnode *devnode = to_media_devnode(cd);
 555         struct media_device *mdev = devnode->media_dev;
 556
 557         return sprintf(buf, "%.*s\n", (int)sizeof(mdev->model), mdev->model);
 558 }
 559
 560 static DEVICE_ATTR(model, S_IRUGO, show_model, NULL);
 561
 562 /* -----------------------------------------------------------------------------
 563  * Registration/unregistration
 564  */
 565
 566 static void media_device_release(struct media_devnode *devnode)
 567 {
 568         dev_dbg(devnode->parent, "Media device released\n");
 569 }
 570
 571 /**
 572  * media_device_register_entity - Register an entity with a media device
 573  * @mdev:       The media device
 574  * @entity:     The entity
 575  */
 576 int __must_check media_device_register_entity(struct media_device *mdev,
 577                                               struct media_entity *entity)
 578 {
 579         struct media_entity_notify *notify, *next;
 580         unsigned int i;
 581         int ret;
 582
 583         if (entity->function == MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN ||
 584             entity->function == MEDIA_ENT_F_UNKNOWN)
 585                 dev_warn(mdev->dev,
 586                          "Entity type for entity %s was not initialized!\n",
 587                          entity->name);
 588
 589         /* Warn if we apparently re-register an entity */
 590         WARN_ON(entity->graph_obj.mdev != NULL);
 591         entity->graph_obj.mdev = mdev;
 592         INIT_LIST_HEAD(&entity->links);
 593         entity->num_links = 0;
 594         entity->num_backlinks = 0;
 595
 596         ret = ida_alloc_min(&mdev->entity_internal_idx, 1, GFP_KERNEL);
 597         if (ret < 0)
 598                 return ret;
 599         entity->internal_idx = ret;
 600
 601         mutex_lock(&mdev->graph_mutex);
 602         mdev->entity_internal_idx_max =
 603                 max(mdev->entity_internal_idx_max, entity->internal_idx);
 604
 605         /* Initialize media_gobj embedded at the entity */
 606         media_gobj_create(mdev, MEDIA_GRAPH_ENTITY, &entity->graph_obj);
 607
 608         /* Initialize objects at the pads */
 609         for (i = 0; i < entity->num_pads; i++)
 610                 media_gobj_create(mdev, MEDIA_GRAPH_PAD,
 611                                &entity->pads[i].graph_obj);
 612
 613         /* invoke entity_notify callbacks */
 614         list_for_each_entry_safe(notify, next, &mdev->entity_notify, list)
 615                 notify->notify(entity, notify->notify_data);
 616
 617         if (mdev->entity_internal_idx_max
 618             >= mdev->pm_count_walk.ent_enum.idx_max) {
 619                 struct media_graph new = { .top = 0 };
 620
 621                 /*
 622                  * Initialise the new graph walk before cleaning up
 623                  * the old one in order not to spoil the graph walk
 624                  * object of the media device if graph walk init fails.
 625                  */
 626                 ret = media_graph_walk_init(&new, mdev);
 627                 if (ret) {
 628                         mutex_unlock(&mdev->graph_mutex);
 629                         return ret;
 630                 }
 631                 media_graph_walk_cleanup(&mdev->pm_count_walk);
 632                 mdev->pm_count_walk = new;
 633         }
 634         mutex_unlock(&mdev->graph_mutex);
 635
 636         return 0;
 637 }
 638 EXPORT_SYMBOL_GPL(media_device_register_entity);
 639
 640 static void __media_device_unregister_entity(struct media_entity *entity)
 641 {
 642         struct media_device *mdev = entity->graph_obj.mdev;
 643         struct media_link *link, *tmp;
 644         struct media_interface *intf;
 645         unsigned int i;
 646
 647         ida_free(&mdev->entity_internal_idx, entity->internal_idx);
 648
 649         /* Remove all interface links pointing to this entity */
 650         list_for_each_entry(intf, &mdev->interfaces, graph_obj.list) {
 651                 list_for_each_entry_safe(link, tmp, &intf->links, list) {
 652                         if (link->entity == entity)
 653                                 __media_remove_intf_link(link);
 654                 }
 655         }
 656
 657         /* Remove all data links that belong to this entity */
 658         __media_entity_remove_links(entity);
 659
 660         /* Remove all pads that belong to this entity */
 661         for (i = 0; i < entity->num_pads; i++)
 662                 media_gobj_destroy(&entity->pads[i].graph_obj);
 663
 664         /* Remove the entity */
 665         media_gobj_destroy(&entity->graph_obj);
 666
 667         /* invoke entity_notify callbacks to handle entity removal?? */
 668
 669         entity->graph_obj.mdev = NULL;
 670 }
 671
 672 void media_device_unregister_entity(struct media_entity *entity)
 673 {
 674         struct media_device *mdev = entity->graph_obj.mdev;
 675
 676         if (mdev == NULL)
 677                 return;
 678
 679         mutex_lock(&mdev->graph_mutex);
 680         __media_device_unregister_entity(entity);
 681         mutex_unlock(&mdev->graph_mutex);
 682 }
 683 EXPORT_SYMBOL_GPL(media_device_unregister_entity);
 684
 685 /**
 686  * media_device_init() - initialize a media device
 687  * @mdev:       The media device
 688  *
 689  * The caller is responsible for initializing the media device before
 690  * registration. The following fields must be set:
 691  *
 692  * - dev must point to the parent device
 693  * - model must be filled with the device model name
 694  */
 695 void media_device_init(struct media_device *mdev)
 696 {
 697         INIT_LIST_HEAD(&mdev->entities);
 698         INIT_LIST_HEAD(&mdev->interfaces);
 699         INIT_LIST_HEAD(&mdev->pads);
 700         INIT_LIST_HEAD(&mdev->links);
 701         INIT_LIST_HEAD(&mdev->entity_notify);
 702         mutex_init(&mdev->graph_mutex);
 703         ida_init(&mdev->entity_internal_idx);
 704
 705         dev_dbg(mdev->dev, "Media device initialized\n");
 706 }
 707 EXPORT_SYMBOL_GPL(media_device_init);
 708
 709 void media_device_cleanup(struct media_device *mdev)
 710 {
 711         ida_destroy(&mdev->entity_internal_idx);
 712         mdev->entity_internal_idx_max = 0;
 713         media_graph_walk_cleanup(&mdev->pm_count_walk);
 714         mutex_destroy(&mdev->graph_mutex);
 715 }
 716 EXPORT_SYMBOL_GPL(media_device_cleanup);
 717
 718 int __must_check __media_device_register(struct media_device *mdev,
 719                                          struct module *owner)
 720 {
 721         struct media_devnode *devnode;
 722         int ret;
 723
 724         devnode = kzalloc(sizeof(*devnode), GFP_KERNEL);
 725         if (!devnode)
 726                 return -ENOMEM;
 727
 728         /* Register the device node. */
 729         mdev->devnode = devnode;
 730         devnode->fops = &media_device_fops;
 731         devnode->parent = mdev->dev;
 732         devnode->release = media_device_release;
 733
 734         /* Set version 0 to indicate user-space that the graph is static */
 735         mdev->topology_version = 0;
 736
 737         ret = media_devnode_register(mdev, devnode, owner);
 738         if (ret < 0) {
 739                 /* devnode free is handled in media_devnode_*() */
 740                 mdev->devnode = NULL;
 741                 return ret;
 742         }
 743
 744         ret = device_create_file(&devnode->dev, &dev_attr_model);
 745         if (ret < 0) {
 746                 /* devnode free is handled in media_devnode_*() */
 747                 mdev->devnode = NULL;
 748                 media_devnode_unregister_prepare(devnode);
 749                 media_devnode_unregister(devnode);
 750                 return ret;
 751         }
 752
 753         dev_dbg(mdev->dev, "Media device registered\n");
 754
 755         return 0;
 756 }
 757 EXPORT_SYMBOL_GPL(__media_device_register);
 758
 759 int __must_check media_device_register_entity_notify(struct media_device *mdev,
 760                                         struct media_entity_notify *nptr)
 761 {
 762         mutex_lock(&mdev->graph_mutex);
 763         list_add_tail(&nptr->list, &mdev->entity_notify);
 764         mutex_unlock(&mdev->graph_mutex);
 765         return 0;
 766 }
 767 EXPORT_SYMBOL_GPL(media_device_register_entity_notify);
 768
 769 /*
 770  * Note: Should be called with mdev->lock held.
 771  */
 772 static void __media_device_unregister_entity_notify(struct media_device *mdev,
 773                                         struct media_entity_notify *nptr)
 774 {
 775         list_del(&nptr->list);
 776 }
 777
 778 void media_device_unregister_entity_notify(struct media_device *mdev,
 779                                         struct media_entity_notify *nptr)
 780 {
 781         mutex_lock(&mdev->graph_mutex);
 782         __media_device_unregister_entity_notify(mdev, nptr);
 783         mutex_unlock(&mdev->graph_mutex);
 784 }
 785 EXPORT_SYMBOL_GPL(media_device_unregister_entity_notify);
 786
 787 void media_device_unregister(struct media_device *mdev)
 788 {
 789         struct media_entity *entity;
 790         struct media_entity *next;
 791         struct media_interface *intf, *tmp_intf;
 792         struct media_entity_notify *notify, *nextp;
 793
 794         if (mdev == NULL)
 795                 return;
 796
 797         mutex_lock(&mdev->graph_mutex);
 798
 799         /* Check if mdev was ever registered at all */
 800         if (!media_devnode_is_registered(mdev->devnode)) {
 801                 mutex_unlock(&mdev->graph_mutex);
 802                 return;
 803         }
 804
 805         /* Clear the devnode register bit to avoid races with media dev open */
 806         media_devnode_unregister_prepare(mdev->devnode);
 807
 808         /* Remove all entities from the media device */
 809         list_for_each_entry_safe(entity, next, &mdev->entities, graph_obj.list)
 810                 __media_device_unregister_entity(entity);
 811
 812         /* Remove all entity_notify callbacks from the media device */
 813         list_for_each_entry_safe(notify, nextp, &mdev->entity_notify, list)
 814                 __media_device_unregister_entity_notify(mdev, notify);
 815
 816         /* Remove all interfaces from the media device */
 817         list_for_each_entry_safe(intf, tmp_intf, &mdev->interfaces,
 818                                  graph_obj.list) {
 819                 /*
 820                  * Unlink the interface, but don't free it here; the
 821                  * module which created it is responsible for freeing
 822                  * it
 823                  */
 824                 __media_remove_intf_links(intf);
 825                 media_gobj_destroy(&intf->graph_obj);
 826         }
 827
 828         mutex_unlock(&mdev->graph_mutex);
 829
 830         dev_dbg(mdev->dev, "Media device unregistered\n");
 831
 832         device_remove_file(&mdev->devnode->dev, &dev_attr_model);
 833         media_devnode_unregister(mdev->devnode);
 834         /* devnode free is handled in media_devnode_*() */
 835         mdev->devnode = NULL;
 836 }
 837 EXPORT_SYMBOL_GPL(media_device_unregister);
 838
 839 #if IS_ENABLED(CONFIG_PCI)
 840 void media_device_pci_init(struct media_device *mdev,
 841                            struct pci_dev *pci_dev,
 842                            const char *name)
 843 {
 844         mdev->dev = &pci_dev->dev;
 845
 846         if (name)
 847                 strlcpy(mdev->model, name, sizeof(mdev->model));
 848         else
 849                 strlcpy(mdev->model, pci_name(pci_dev), sizeof(mdev->model));
 850
 851         sprintf(mdev->bus_info, "PCI:%s", pci_name(pci_dev));
 852
 853         mdev->hw_revision = (pci_dev->subsystem_vendor << 16)
 854                             | pci_dev->subsystem_device;
 855
 856         media_device_init(mdev);
 857 }
 858 EXPORT_SYMBOL_GPL(media_device_pci_init);
 859 #endif
 860
 861 #if IS_ENABLED(CONFIG_USB)
 862 void __media_device_usb_init(struct media_device *mdev,
 863                              struct usb_device *udev,
 864                              const char *board_name,
 865                              const char *driver_name)
 866 {
 867         mdev->dev = &udev->dev;
 868
 869         if (driver_name)
 870                 strlcpy(mdev->driver_name, driver_name,
 871                         sizeof(mdev->driver_name));
 872
 873         if (board_name)
 874                 strlcpy(mdev->model, board_name, sizeof(mdev->model));
 875         else if (udev->product)
 876                 strlcpy(mdev->model, udev->product, sizeof(mdev->model));
 877         else
 878                 strlcpy(mdev->model, "unknown model", sizeof(mdev->model));
 879         if (udev->serial)
 880                 strlcpy(mdev->serial, udev->serial, sizeof(mdev->serial));
 881         usb_make_path(udev, mdev->bus_info, sizeof(mdev->bus_info));
 882         mdev->hw_revision = le16_to_cpu(udev->descriptor.bcdDevice);
 883
 884         media_device_init(mdev);
 885 }
 886 EXPORT_SYMBOL_GPL(__media_device_usb_init);
 887 #endif
 888
 889
 890 #endif /* CONFIG_MEDIA_CONTROLLER */